Apple has announced plans for 'special voluntary audits' of factories run by
Foxconn, the Taiwanese firm that manufactures Apple products.

The Fair Labour Association has begun inspections at Foxconn's Shenzhen factory and will also assess the factory in Chengdu. At Apple's request, the FLA will inspect facilities, interview employees and inspect documentation to ensure that proper procedures are followed.

Later this Spring, the FLA will audit factories run by Quanta and Pegatron. Apple says that when the full audit is completed, it will have covered the facilities where more than 90 per cent of Apple's products are assembled.

“The inspections now underway are unprecedented in the electronics industry, both in scale and scope, and we appreciate the FLA agreeing to take the unusual step of identifying the factories in their reports," said Tim Cook, Apple's chief executive, in a statement.

The announcement comes a week after petitions were delivered to Apple stores in London, New York, Washington DC, San Francisco, Sydney and Bangalore, calling on Apple to improve conditions for workers in China.

Apple has monitored its suppliers since 2006 and publishes detailed annual reports that set out the extent to which each supplier complies with Apple's rules on issues including health and safety, workers' rights and environmental impact.

Though the company points to improved standards across its supply chain since it began monitoring its suppliers, critics want Apple to do more.

Last month, In an email to Apple staff that was leaked to media, Cook said: "Any suggestion that we don't care is patently false and offensive to us. As you know better than anyone, accusations like these are contrary to our values. It's not who we are."

As well as Apple, Foxconn manufactures products for Sony, Microsoft, Amazon, Motorola, Dell, IBM, Nokia and Toshiba, among others.

In January, Apple became the first technology company to join the FLA, which was founded by Nike in the 1990s and monitors conditions for workers across the world.